Mounting a point motor

To make the job of mounting the new points on the layout easier, I’m experimenting with a method of attaching the point motor directly to the point, allowing the whole assembly to just be dropped into a suitable hole on the layout.

The first stage is to glue some thin plastic to the point sleepers – I used a bit of case from an old 8″ floppy disk (left over from the very early days of computing…):The plastic is wider than the hole will be, so should cover any gaps. There is a small gap in the plastic to allow the control wire to move the tie bar.

On the underside, a 38mm x 50mm piece of 6mm plywood is glued to the plastic, and the point motor (Conrad) screwed to this (1.5mm hole). The screws are too long for the plywood, so the excess are trimmed:
Wires from the point frog and rails are soldered to small pins in the wood. This allows a switch inside the point motor to change the frog polarity:
Two more pins allow a connection to the point motor itself:You can just see a spring steel wire on the right, which connects the moving arm of the point motor to the tie bar on the point.

Finally, wires are attached to the pins; the red ones will go to the point motor driver, the other pair to the track power:

Update 1
I’ve used a different arrangement for the spring steel wire on subsequent points:

This uses a much thinner wire (the thin wire supplied with the motor), constrained by the short copper tube under the motor. This produces enough force to move the point, but no so much that the point could be damaged should a problem occur.

Update 2

More point motors have now been fitted, and this photo shows a neater method for the construction and wiring. This motor is fitted a 6mm plywood base on 1.5mm black plasticard, with the point glued to the other side. This should match the height of the 1/16″ cork overlay, providing a constant top surface on the layout itself. Note that the wires are taken around the opposite side of the motor to the actuator wire.

Note the thin red wires on the right that take the power to the point and frog.

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